Slope Stability Risk Management in Open Pit Mines: A Hazard Zonation Investigation Along Jwaneng Mine CUT-8 Haul Roads

 Rockfalls present a major safety hazard in open pit mining, predominantly in large scale deep pits. Generally, slopes of an open pit mine are excavated to the steepest angle possible. Steeper slope angles are economic; however, they result in an increased risk of slope failure in combination with other causative factors. Geotechnical zoning allows accurate risk prediction for potential loss of stability elements at different stages of the pit development.

 The failure of these slopes is a result of factors such as slope geometry (angle & height), type of lithology, geological discontinuities, seismicity, etc.

 Evaluation of the stability of excavated slopes is a vital component of any open pit mine and for smooth operations.

Summary of outcome

- Demarcated regions and areas of potential slope failure within the mining areas.
- Determined Slope Stability Index from ‘suitable hazard zonation techniques such as (Bureau Indian Standard 1998 , Mine Slope Instability Index 2013 and Slope Mass Rating (SMR) and Falling Rock Hazard Index (FRHI)
- Detailed “kinematic analysis” on high hazard level areas.
- Determined relationship for causative dominant parameter and slope instability.
- Determined hazard zonation technique validity by comparing the slope behaviour in reality versus predicted behaviour.

Hazard Zonation Map of the Jwaneng Cut 8 Haul Road